Jumping rope is an activity that is performed by people of various ages and fitness levels since it builds coordination and provides an aerobic workout. Jumping rope can strengthen legs, arms and shoulders. In jumping rope, the impact of each jump is absorbed by both legs. Therefore, jumping rope is considered by some to be low impact activity. As a low impact activity, the risk of knee injury to the person resulting from the impact of the jump is reduced. While the risk of knee injury may be reduced, other injuries may result from the person selecting a jump rope that is either too long or too short.